Printing press



Sept. 12, 1944.

w. w. DAVIDSON ETAL PRINTING PRESS Filed May 24, 1941 3 Sheets-Sheet 1 INVENTORS m M W Sept. 12, 1944. w w DAVIDSON ETAL 2,358,284

PRINTING PRESS Filed May 24, 1941 3 Sheets-Sheet 2 INVENTORS William Ward .Ddl/LdSO/Z BY Edward Iflzll M M if 5 TTY p 1944- w. w. DAVIDSON ETAL 2,358,284

PRINTING PRESS Filed May 24, 1941 3 Sheets-Sheet 3 INVENTORS ifilla/n Wa/uflaw'dso/z BY Edward ['7 fie 14 m AW Patented Sept. 12, 1944 UNITED STATES PATENT OFFICE PmN'rING rlmss' William Ward Davidson, Evanston, and Edward F. Dell, Park Ridge, 111.; said Dell assig'nor to Davidson Manufacturing Corporation, Chicago, 111., a corporation of Illinois ApplicationMay 24, 1941, Serial No. 395,078.

12 Claims.

print satisfactorily and conveniently either by.

direct letter-press printing, by which is meant printing from-raised inked surfaces such as type, or offset planographic printing, by which is meantprinting from a smooth planographic surface onto a transfer blanket and from it onto the sheet to be printed.

One of the features of the invention which is important in respect to economy and convenience is in providing an inexpensive construction in which prints produced by either direct or ofiset printing can be delivered right-side-up for inspection. According to the present invention, this is accomplished by having the blanket roll above the larger roll which carries both the plate and platen surfaces for offset printing, and using this same upper roll as the type-carrying roll for direct printing. Thus, the printing is always done on the upper surface of the sheet, so that the sheet never needs to be turned over for right-side-up delivery and hence may be ejected to the catcher or collecting box with the utmost simplicity. It will be observed, however, that this requires inking the large lower roll for oilset printing and inking the upper roll for.

direct printing. According to the present invention, this has been accomplished without loss of the desired economy by providing an inking mechanism which may easily be shifted from the lower roll to the upper roll and which will operate in either position with a minimum of connections with the rest of the press. In short, the inking mechanism is made in a substantially complete self-contained unit.

The location of the blanket roll at the top has the advantage of rendering it unusually accessible for cleaning and inspection.

The press utilizes a relatively small number of inking rolls with the result that even when these inking rolls are positioned below the larger lower roll, they do not extend downwardly therefrom far enough to be inconveniently low.

Additional objects and advantages of the invention will be apparent. from the following description and from the drawings, in which:

Fig. lis a diagrammatic view of the presschosen for illustration of the invention, arranged for offset printing.

Fig. 2 is a somewhat less diagrammatic view on a larger scale, showing details of the dampening and inking units and showing various other controls diagrammatically,

Fig. 2a is a fragmentary view of a different form of platen that may be used in this invention.

Figs. 3 and 4-are views corresponding to Figs.

1 and 2 but showing the press arranged for a direct printing.

Fig. 5 is a diagrammatic view illustrating the fact that the axis of the inking roll in Figs. 3 and 4 is in the same position whetherthe cooperating type roll is in printing engagement with the other printing roll or not.

Fig. 6 is a somewhat diagrammatic plan view of the structure shown in Fig. 4.

Fig. 7 is a view taken approximately on the line l'i of Fig. 6. 1

Fig. 8 is a fragmentary view showing particularly the operation of the ductor roll.

Fig. 9 is a fragmentary detail view taken approximately on the line 99 of Fig. 8.

Fig. 10 is a fragmentary detail view taken on the line lt-IU of Fig. 9.

A preferred form of the invention has been chosen for illustration and description, in compliance with section4888 of the Revised Statutes, but persons skilled in the art will readily perceive other means for accomplishing the same results, and the claims are therefore to be construed as broadly as possible, consistent with the prior art.

' GENERAL ORGANIZATION Before considering the detailed structure of A. Lithographic ofl set printing The sheet of paper A in Fig. lwas delivered by any suitable sheet-separating means or by hand to a diagonal tape-conveyor board D, by which it was fed against a'suitable side guide ing cylinders, the stop fingers the way as the rollers rotate.

for lateral registration and against suitable stop fingers E (Fig. 2) which at the time were vertically positioned. The stop fingers E stop the sheet with its leading end between the feed rollers H, which close upon; the sheet and grip it while the sheet is still stationary, and then rotate to move the sheet toward the bite of the print- E moving outof During this process of bringing the sheet A to the bite of the cylinders, the lower or larger cylinder or roll I which carries a plate J on one. periph- Serial No. 164,546, the disclosure tr which is hereby made a part hereof byreference. As

; diagrammatically indicated in,Fig. 2, the upper feed roller H-.is raised and lowered by a cam' I I, and, after it has been lowered to press a sheet against the lower feed roller H, thisroller is started smoothly by a rack I2 controlled by cam cam I3 will be shaped to over-feed the sheet A eral segment and a platen surface K on another peripheral segment has been rotated to ink up the plate J and apply the image .to the blanket it isready to be applied tothe sheet when it reachesthe bite of the printing cylinders. Cylinder I rotates in a counterclockwise direction, as

seen in Fig. 1, so that the plate J is first dampened by the dampening unit N so that;when it reaches the inking unit 0', the ink will stick only to the image portion of the plate. Between the printing of successive shetsthe plate J rotates in contact with the blanket L and applies its lithographic image to the blanket L, On the next half revolution of the large drum or cylinder I the gripper Qreceives and grips the leading edge .of the sheet A and carries it through the bite between the blanket L and the platen segon the upper face of the sheet. In, feeding the sheet to the gripper Q, the feed rollers H feed it slightly faster than the peripheral speed of the printing'cylinders topress it into registration against stop fingers associated with the grip- -ment. K so that the. blanket.prints the image per Q. The gripper Q releases the sheet in time continuously rotating to break up. the ink and 4 replenish the ink on the ink form roller for the next application of ink to the printing plate.

B. Direct letter-press printing For direct printing, the press is changed as shown in Fig. 3. A type-bearing member U is substituted for the blanket L on the blanket cylinder M, and the inking unit Ois moved, to the upper left-hand corner of the press, as seen in Fig.3, so that its form roller will engage the type face on the typographic member U. The typographic member U may conveniently comprise a rubber plate, the maximum effective thickness of which is the same as that of the blanket. According to present commercial practice, this is of an inch. If the platen is suitable for use with a metal plate, as indicated in Fig. 2a, the a M will continuev to print on the upper face of the' sheet A which is carried by the platen K as before. The sheet will be delivered to the same collecting 'box or catcher P as in'Fig. 1 and still willbe delivered printed-side-up.

Fsnnmo APPARATUS The feeding apparatus may be substantially the somewhat-so as to buckle it slightly against the registration stop fingers I4 associated with the gripper Q. The gripper Q is opened by cam l8 toreceive the sheet and is closed on the sheet 0 the sheet from the press and deliver same as that illustrated in copending application I 5 before the sheet leaves the feed rollers H. L carried on the smaller upper cylinder M, where EJEcrnvo MECHANISM jI'hegripper Q continues to grip the sheetuntil the leading end has passed under an ejector roller l8. While plate J is passing under ejector roller I8, the ejector roller is held away from the plate by cam I9. Aftenthe leading edge oi the sheet passes under the ejector roller ill, the springurged roller l8,is lowered onto the sheet by cam 19 and the gripper Q opens wide enough to allow the leading edge of the sheet to escape therefrom.

The leading edge of the sheet flies out to engage the outer side of the stripper 2| so that the strip-.

" per 2| and the ejector roller l8 reliably remove it to the catcher or collectingbox P. v

Dsmramne UNrr In lithographic printing; the plate J must be dampened before it is inked. The image on the therefore will not stick to, the image portion of the plate but it does wet the remainder of the l The ink thenfiw'illnot stick to the wet- 40 portion of the plate, and soonly tion of the plate is inked.

plate.

the image por- Dampeningunits conventionally include a fountain or pan 26 for the dampening liquid (which is mostly water), a fountain roll 21, a ductor roll the distributor roll 29, in which position it passes the dampening liquid on to that roll, which passes it to the form roller 30.

According to the present invention, the operation of these various rolls is very simple. The dampening form roller 30, distributor roll 29, 'and doctor roll 28 when in contact with the distributor roll 29 are all driven by the contact of the roller 30 with the plate J. The ductor roll 28 is shifted by a cam 3| in Fig. 4, which actuates a cam follower 32 on a lever 33 rigidwith shaft 34 on which are rigidly mounted the ductor roll supporting arms 36. The cam 3| is driven .by a sprocket 31 and chain 38 from a-sprocket 39 rotating rigidly with the larger cylinder I. Sprockets a1 and 39 have the same number of teeth' so that cam 3| rotates synchronously with cylinder I. It is thus seen that the ductor roll during each revolution ofthe cylinder 1.

plate is a greasy image and the dampening water 28, a distributor roll 29, aiid dampening form ductorroll 28 shifts back into engagement with- 28 is shifted against the fountain roll 21 once The fountain roll 21 is also actuated by the chain 88 so that this chain is the only special driving connection required between the dampening unit N and the rest of the press. A ratchet 4| is mounted in rigid relationship to the fountain roll 21 and is actuated by a pawl 42 carried by a lever 43 pivoted concentrically with theratchet 4| and actuated by a link 44 from crank disc 45 which is driven jointly with cam 3| by the sprocket 81. According to conventional practice, an adjustable slide may be interposed between pawl 82 and ratchet 4| to vary the portion of the stroke of the pawl 42 during which it is free to engage the ratchet 4|. This will determine the angular movement of the fountain roll 21 during each cycle of the press.

Some of the dampening rolls, preferably rolls I8 and 88, are coated with a conventional absorbent covering, and pinion 46 meshes with gears on the cylinder 1 and on distributor roller 28 to drive the dampening roller even when form For the sake of uniformity it is desirable t the ductor roll 82 remain in contactwith the fourititin roll 5| during the entire movement of the fountain roll. During this movement, and in fact during the entire first stroke of rack 88 from the Fig. 8 position, the ductor roll 52 is held in'contact withthe fountain roll ill by virtue of aspring'll, seeninFig. 4. q I i In the returnstroke 'of rack 86, during which the ink fountain roll 5| is idle, the ductor roll 52 must be moved against the distributor roll 58, new against it for a substantial time, and returned to the ink fountain roll 5| This is accomplished by one revolution of a cam 12 against which'cam follower I3 is held by spring 1|. The cam 12 is given this one revolution rotation -.by pinion 61, which is now rotating clockwise as seen in Fig. 8 and which in thisdirection' ofrotation drives cam I2 through dog 14. Dog -18 is carried by a collar 15 on the hub of which 'the cam is rigidly mounted. The dog I4 enroller 38 is not in contact with the, plate, thus assuring an even distribution of the dampening liquid.

The fountain is preferably made of porcelain, as this will avoid any electrolytic action between it and the dampening liquid.

INKING UNIT Because the inking unit 0 is shifted from theposition shown in Fig. 2 to the position shown in Fig. 4, it is desirable that its actuation be as simple as possible. According to the present invention, it is only necessary to change one link when it is moved. In the position shown in Fig. 2, the link 56 is used, while in the position shown in Fig. 4 the link 51 is used. In both instances the link connects a, crank disc 45 with the pivoted plate or lever 58 which carries the pawl 59. The pawl 59 engages the ratchet 5| on the ink fountain roll 5|. Thus, for each cycle of the press the ink fountain roll 5| .is rotated through an angular distance corresponding to a gages a notch in disc 11 rigid with pinion 61. Preferably there is only one notch in the disc 11 so that it will always turn the dog 14 and the cam-12 to the same position. The notch is, of course, ratchet-shaped so that it willdrive the dog onlyin one direction. The dog ll may either be urged inwardly by a spring or it may come to rest above-the disc 11 each time so that it will fall into the notch by gravity, being held therein during driving by-the shape of the notch. The movement of the rack 66 is enough to give the pinion 61 one complete revolution or slightly certain number of teeth on the ratchet 6|.

According to conventional practice, this number of teeth is variable by an adjustable slide, not shown, which holds the pawl 59 out of engagement with the teeth of ratchet 5| during any desired part of the movement of the pawl 58.

According to the present invention, the shifting of the ductor roll 52 is effected through the same link 55 or, in Fig. 4, 51. The manner in which this is accomplished is best seen by reference to Figs. 8 and 9. A rack bar 66 is pivoted to the pawl-carrying plate 58 and drives a pinion 61 in opposite directions, the rack being held in engagement with the pinion by rollers 68 on pivoted plate 68 (Fig. 9).

With the parts starting in the position shown in Fig. 8, the pinion 81 will rotate counterclockwise upon movement of the rack 66 to'the right. This counterclockwise movement of the pinion 01, however, is an idle movement and no movement is transmitted by it. During this movemerit the pawl 58 drives the ink fountain roll 5|.

morewith each stroke of the rack 66.

It is desirable that the inking distributor and form rollers'rotate all of the time whether in contact with the plate or not, and accordingly 9. gear 18 is provided for the Fig. 2 position of the inking mechanism and a. gear 79 for the Fig. 4

position. Each of these gears meshes with a gear driven with the printing surface being inked and also a. gear in rigid relationship with one of the inking rolls. Thus, as seen in Figs. 4 and 6, the gear 19 meshes with gear 8|, which is the drive gear for cylinder M, and with gear 82 rigid with ink distributor roll53. The size-of the gear 82 is, of course, such as to give the form inking roller 58 the same peripheral speed as the surface being inked.

It will be observed that as the inking unit is shifted from one position to another, thegear 82 automatically comes into engagement with either the gear '88 or,thegear is so that no attention at the right in Fig. 7 and near the bottom in Fig.

6, the shaft 88 carries a roller 89 which is pivoted to the shaft 88 with an axis which is radial with respect to the shaft 88. The roller 89 rides in a cam slot 9| in a sleeve 92. Thesleeve 92 is slidable on shaft 88 but is prevented fromrotating thereon by a vane 93 projecting into a slot in the sleeve 92, as seen best in Fig. 7. The vane 93 is rigidly mounted on the press frame, or on the bearing for shaft 88 carried by the frame.

As the shaft 88 is rocked back and forth by the surface Kl at the new position, and apply the link 51-. the ink unit is at the right of the press, as seen I "1m: 55 and crank arm 81, the roller 5 5 moves from one end of the slot 8| to the other, and, since 'ating cylinder.

and forth, it also oscillates the roll 53 back and forth along the shaft 88, thus giving the roll 55 the desired sliding movementl. On account of this oscillating sliding movement, the roll 53 is often called the vibrator roll.

The form roller 54 is carried by a shaft 85 which is mounted in hub 91 of pivoted hangers 98 rotatable on the shaft 88. Springs 99 urge the hangers '98 in a directionto press the roller 54 against the surface to be inked. While the platen surface K is passing under the ink roller 54, as seen in Fig. 2, the ink roller 54 is held out of contact with the platen surfaceKby cam sur-.-

faces I| at the margins of the platensurface K and follower rollers I02 onshaft 95. It may be noted that the dampening form roller 30 is similarly mounted and similarly held off of the platen the handle I in Fig, .7. The cam I03 is so shaped that in diffe'rentjpositions it will hold tion from that shown in the Fig. 2 position. This is permitted by the mounting of the roller 54 and it will be observed that in each instance. the roller 54 is urged in the proper direction against the surface being inked in spite of the changed relationship between the inking unit and its cooper- The changed arrangement of rolls provides maximum visibility of the collection box in the Fig. 4 position and maximum accessibility of the ink fountain in the Fig. 2 position where accessibility presents a problem. Although the spring 99 is under greater tension in Fig. 4

. thanin Fig. 2, this does. not affect. the inking eitheror both of its associated rollers 30 and 54 out of the active position or will'let either or both assume its active position. Screws I05 may be provided .for regulating the pressureof the respective rollers 30 and 54 on the surface being inked, or the strength of the springs urging them into contachmay be predetermined toprovidc this pressure. To avoid disturbing the adjustment of .the inking pressure control screw I06 when-the inking unitis shifted from the Fig. 2

'position to the Fig. 4 position, cam I04 may be provided with means to adjust the angular position to which it may be returned after moving it to its throw-out position. j

Srurrmc or THE INKmc Umr 55, loosen the securing bolts III, slide the whole unit out of the frame and slide it into the frame Since in Fig. 2, and at the leftwhen in the new position about a vertical axis so that, although the cylinder M rotates in the direction opposite to the dishown in Fig. 4, it has in effect been pivoted 180 rection of cylinder I, the movement of the parts for adjusting the distribution of ink feed along the length of fountain roll 5|.

It will also be observed that the arrangement of the inking rolls is different in the Fig. 4 posipressure since this pressure is determined by. the adjustment of screw I05.

, THROW-Our It is, of course, desirable that at times the cylinders I and M be separated so that, when the press is rotating without sheets being fed, the

spring III, may be moved in the opposite direc-. tion by the handle H8, and is latched in the printing position by arm I I9 and latch I20. Latch I20 is in turn provided with a handle I2I for releasing the latch to cause a throw-out movement of shaft Il-B under influence of the spring III:

An important point to be noticed is seen best in Fig. 5, from which it will be observed that in the two positions of the cylinder M the distance between its axis and the axis of the roller 54 is the same; The position of the axis of the roller-54 .is,"of course, determined by the'cam I04 and screw By virtue of having the distance between these axes the same in both positions of the cylinder M, the inking pressure will be the same inboth positions so that the cylinder M may be properly. inked up while it is rotating in the throw-out position. i

It is desirable that the ductor roll 52 shift a ainst the vibrator roll 53 at the earliest moment .in the cycle of the press which will not result in this freshly applied ink being carried to the plate or type without being first broken up. Due to the differing positions of the parts, this earliest possible moment does not occur at the same time in the Fig. 4 arrangement as in the Fig. 2 arrangement. However, the driving of the pivoted plate 58 from different crank discs 45 in the two I instances makes it possible to provide exactly the correct timing in both instances. This is accomplished merely by setting each of the crank discs 45 with its pin in the proper position to actuate the plate 58 at the right time for the parts, considering the dimensions of the parts and their relative positions. to select this positioning for the crank discs 45 in the drawings since the correct positioning is. most easily determined with an-actual machine. In brief, the discs 45 should be set in such position that after the ductor roll 52 applies'fresh ink to the roll 53, this ink will be carried around the roll 53, passed in part to the roll 54. and carried around the roll 54 to reach the position of the bite of the roll 54 with the plate J Just after the plate J passes out of contact with the roll 54. This gives the maximum time during which rotation of the rolls 52, 53 and 54 will break up and distribute the ink before fresh ink can be applied to the plate. As previously indicated, the

No attempt has been made of the ink unit.

Under some circumstances it is not necessary to move the ink unit at all in order to print by direct printing from rubber type on the cylinder M. Such printing can be accomplished, by the use of the invention of Davidson copending application Serial No. 347,454, by replacing the plate J with. an unetched plate and using this plate as the form roller for the rubber type on cylinder M. The cam I03 is turned to a position to keep the dampening unit out of contact with the plate,

and the roller It applies ink over the entire surface of the plate. This ink is in turn applied to the raised surfaces of the rubber type plate which prints on the upper face of the sheet.

The shifting of the ink unit is particularly important when a metal type plate is to be used on cylinder M because such plate probably cannot be satisfactorily inked b a metal inking roller such as would be formed by the unetched plate in place of the plate J.

' Printing with a metal plate on the solid metal platen segment K is likely not to be very satis-. factory. Accordingly. it will usually be preferred to provide a platen of the general type illustrated in Fig. 2a, in which the main part I 28 of the platen segment is of slightly smaller radius than that shown in the other figures and an overlay I2! is used to provide the proper surface characteristics and to build the platen out to the proper radius. The overlay may comprise any conventional tympan, or brass sheet of /1000 to "/1000 of an inch thickness with suitable underlays or a tough rubber blanket made of a blanket which is somewhat harder than conventional lithographic blankets so that the type will not mar the sheets by pressing into the blanket excessively. In some instances the brass sheet with its underlays will be preferred because the underlays may be removed in accordance with the thickness of the' sheet to be run. This will avoid printing imperfections due to improper radius and also avoid the necessity for any ready adjustability of the cylinders to provide for maintaining the right printing pressure with different thicknesses of sheet. If such adiustability is provided, however, the relatively hard rubber blanket may be preferred since the proper hardness of platen blanket will be entirely satisfactoryv to serve both as a lithographic platen and as a letterpress platen, whether the raised letter-press image be formed of rubber of metal. If a brass sheet is preferred for the lithographic printing, it may be replaced by the blanket. Since the blanket will be thicker than the brass sheet, it will probably be necessary to remove some underlay with the brass sheet. It will be observed that with either of these arrangements the cylinders themselves need never be changed but it will only be necessary at most to remove or change the surface members on the plate, blanket roll and platen. In fact, it will not even be necessary to change the platen surface, at least if the relatively hard rubber blanket is used for this surface all the time. By moving the inking unit, the

, proper ink form roller for metal is provided at the proper place so that for satisfactory printing it is only necessary to have a proper platen surface.

From the foregoing it is seen that a press has been provided in which the upper side of the sheet is printed either with offset lithographic expensive to manufacture for a high quality, twopurpose press since it is not necessary to provide any means for turning over the sheet with either method of printing nor is it necessary to provide any extra inking unit for either method of printing, the single inking unit being interchangeable between two positions for the two methods of printing. All of the essentials to high quality printing have been retained.

We claim:

1. A printing press for printing the upper face of a sheet optionally by a raised image method or an offset lithographic method including a smaller upper cylinder and a larger lower cylinder having a platen segment and a plate segment thereon adapted to receive a plate, dampening means for the plate, an inking unit for the plate adapted to apply paste ink thereto and having a plateengaging roll and including a fountain roll, a second roll and a ductor roll shiftable between the fountain roll and the second roll, and means actuated by a single lever for driving the fountain roll intermittently and shifting the ductor roll in synchronism therewith; said upper cylinder being adapted to have a transfer surface thereon for receiving an image from the plate and transferring it to the upper face of a sheet on the platen, and being adapted alternatively to have a direct printing member thereon with a raised image adapted to print the upper face of a sheet on said platen with paste ink, and means for detachably mounting the inking unit alternatively at two positions to cause the plate-engaging roll thereof to engage the direct printing member on the smaller cylinder or, alternatively, the surface of the plate.

2. A printing press for printing the upper face ring it to the upper face of a sheet on the platen,

and being adapted alternatively to have a direct raised image printing member thereon to print the upper face of a sheet .on said platen, and means for detachably mounting the inking unit alternatively at two positions to cause the plateengaging roller thereof to engage the direct printing member on the smaller cylinder or, alternatively, the surface of the plate; said inking unit being adapted tocooperate with either size of cylinder and in each position being adapted to apply a paste type of ink.

3. A printing press for printing the upper face of a sheet optionally by a raised image method or an offset lithographic method including a smaller upper cylinder and a larger lower cylinder having a platen segment and a plate-bearing segment thereon, dampening means for the plate', and inking means for the plate comprising a plurality of ink rollers one of which rotates in contact with the plate, said upper cylinder being adapted to have a transfer surface thereon for receiving an image from the plate and transferring it to the upper face of a sheet on the platen, and being adapted alternatively to have a direct printing member thereon with transfer medium, and a platen, mounted on cylinders with bites formed by the plate and the transfer medium'and by the transfer medium and the platen, dampening and inking means for the plate comprising a dampening fountain roll, an ink fountain roll, dampening distributor and form rollers, ink distributor and form rollers, a dampening ductor roll, an ink ductor roll, a member driven in synchronism with one of the cylinders, linkage driven uniformly by said member connecting said member to rotate the fountain rolls during a part of the cycle, and means for operating the ductor rolls to position them alternately on the fountain rolls andon the distributor rolls, the means for operating the ink ductor roll being actuated by said linkage and shifting the ink ductor roll only while the ink fountain roll is stationary.

5. A printing press including a smaller upper cylinder and a larger lower cylinder havin aplaten segment and a plate-bearing segment thereon, dampening means for the plate, and

inking means for the plate comprising a plural ity of ink rollers one of which rotates in contact with the plate, said upper cylinder being adapted to have a transfer surface thereon for receiving an image from the plate and transferring it to the upper face of a sheet on the platen, and being adapted alternatively to have a direct printing member thereon to print the upper face of a sheet on said platen, and means for detachably mounting the inking unit alternatively at two positions one below the center of the lower cylinder and the other above the center of the upper cylinder, and said inking unit having its plate-engaging roller resiliently urged in a given direction but 'shiftable through a wide angle so as to be urged toward the cooperating cylinder in each position 'of the inking means with the remainder of the or an offset lithographic method including a printing couple comprising a smaller upper cylinder and a larger lower cylinder, the larger cylinder having a platen surface and a plate surface, and the upper cylinder being adapted to have a transfer surface and receiving the image from the plate and printing it on the upper face of v the sheet against the platen, and being adapted alternatively to have a raised image surface thereon an inking unitmeans for detachably mounting the inking unit alternatively at two positions to engage alternatively the plate surface of the lower cylinder or the raised image surface of the .upper cylinder; said inking unit being adapted to cooperate with either size of cylinder and in each position. being adapted to apply a paste type of ink.

'7. A printing press having thereon two cylinders either of which may hear an image surface to be inked, an inking unit means for detachably mounting the hiking unit alternatively at two positions in one of which it inks the image surface on one cylinder and in the other of which it inks the image surface on the other cylinder, and means for driving said inking unit includ-' ing a shaft driven in synchronism with one of the cylinders, crank member on opposite ends of the shaft adjacent opposite sides of the press, and link means adapted to cooperate with one of the crank members for one position of the inking unit and with the other crank member for the other position of the inking unit, the inking unit in being moved from one position to the other. being turned end for end so that attach ment of the link means is made to the crank member on the opposite side of the press.

8. A printing press having thereon two cylinders either of which may bear an image surface to be inked, an inking unit, means for detachably mounting the inking unit alternatively at two positions in one of which it inks the image surface on one cylinder and in the other of which it inks the image surface on the other cylinder, and means for driving said inking unit consisting, except for parts moved with the inking unit, solely in gears automatically meshed in each position as the inking unit is moved into positim, and link means for a single connection with its driving mechanism comprising a shaft driven in synchronism with-one of the cylinders, crank members on opposite ends of the shaft adjacent opposite sides of the press, the link means being adapted to cooperate with one of the crankmembers for one position of the inking unit and with the other crank'member for the other position of the inking unit, the inking unit inbeing movui from. one position to the other, being turned end for end so that attachment of the link means is made to the crank member on the opposite side of the press.

9. A printing press including a smaller upper cylinder and a large lower cylinder having a platen segment and a plate segment thereon adapted to receive a plate, dampening means for the plate, an inking unit for the plate having a plate-engaging roll and including a fountain roll, a second roll and a ductor roll shiftahle between the fountain roll and the second roll, and means actuated by a single lever for driving the fountain roll intermittently and shifting the ductor roll only while the fountain roll is stationary; said upper cylinder being adapted to have a transfersuri'ace thereon for receiving an image from the plate and transferring it to the upper face of a sheet on the platen, and being adapted alternatively to have a direct printing member thereon with a raised image adapted to print the upper face of a sheet on said platen, and mean; for detachably mounting the inking unit alternatively at two positions to cause the plate-engaging roll thereof to engage the direct printing member on the smaller cylinder or, alternatively, the surface of the plate.

10. A printing press having thereon two cylinders either of which may hear an image surface to be inked, andnklng unit, means for detachablymounting the inking unit alternatively at two positions in one of which it inks the image surface on one cylinder and in the other of which it inks the image surface on the other cylinder, and means for driving said inking imit m ing of drive means driven with the press and stationarily located, and drive parts movable with the inking unit as it is shifted including gear means automatically meshing in each position as the inking unit is moved into position, and link means for a single connection in each position with the drive means, said gear means and said link means being the sole driving connections for the inking unit.

11. A printing press having thereon two cylinders either of which may bear an image sur--' face to be inked, an inking unit, means for de-, tachabiy mounting the inking unit alternatively at two positions in one of which it inks the image surface on one cylinder and in the other of which it inks the image surface on the other cylinder, and means for driving said inking unit in either position; said inking unit being positioned substantially above the bottom of the cylinder in tally against the surface being inked in the other position.

12. A printing press having thereon two cylinders either of which may bear an image surface to be inked, an inking unit, means for detachably mounting the inking unit alternatively at two positions in one of which it inks the image surface on one cylinder and in the other of which it inks the image surface on the other cylinder,

and means for driving said inking unit in either position; said inking unit being positioned higher angularly about the axis of the cooperating cylinder in one position than in the other, and said inking unit including a distributor roll and a form roller shiftable angularly about the distributor roll to bear at one angle against the surface being inked in the last-named position and to bear at another angle against the surface being inked in'the other position.

WILLIAM WARD DAVIDSON. EDWARD F. DELL. 

